In performing knee arthroplasty with conventional knee prostheses, it has been necessary to form large incisions in order to accommodate the preparation of the femur to receive the prosthesis and to accommodate the reception of a fairly large prosthesis into the incised femur for implantation on the prepared distal end of the femur. As is appreciated by those skilled in the art, it is desirable to minimize the size of any incision as the smaller the incision, the more rapidly the patient may recover. Prior art prostheses formed with a single piece metal component having both left and right condylar portions integral with the patellar flange area require large incisions in order to accommodate implantation in the prepared femur. In contrast, under the present invention, through the use of multiple pieces for the femoral component, it is possible to greatly reduce the size of any such incision, thereby reducing the amount of damage to soft tissue from any such arthroplasty and speeding the time of recovery. Similarly, it is desirable to minimize the size of any incision in the tibia during any implantation of the tibial component.